WWW 8m United States Patent 3,711,256 GAS CONDITIONING APPARATUS WITH BAFFLES AND DRYER UNIT Will B. Williams, Oakland, Calif., assignor of a fractional part interest to Harry J. Benson, San Leandro, Calif. Filed Dec. 15, 1970, Ser. No. 98,402 Int. Cl. B01f 3/02 US. Cl. 48-180 R 6 Claims ABSTRACT OF THE DISCLOSURE A mixing tank or chamber having an inlet communicated with a source of dried air at a predetermined pressure and an inlet communicated with a source of natural or manufactured gas at a predetermined temperature with the tank or chamber having a plurality of spaced baffies therein and screen material to thoroughly mix and intermingle the gas and air to provide a homogeneous combustible mixture for discharge to a gas burning device such as a furnace, boiler or the like.

BACKGROUND OF THE INVENTION Field of the invention The present invention generally relates to a gas conditioning apparatus incorporating a mixing chamber having baflies and screen material associated therewith for thoroughly mixing gas and air with the apparatus also including a drying device for the air to remove entrained moisture in the air with the structure disclosed in this application being an improvement on that disclosed in my co-pending application Ser. No. 845,771 filed July 29, 1969 for Gas Conditioning Apparatus now abandoned.

Description of the prior art Previously, various devices have been provided which have introduced a quantity of air into the gas supply for providing a combustible mixture. However, such devices have been unsuccessful inasmuch as previously known devices have resulted in imperfect or uneven mixing of the air and gas, entrainment of moisture in the air and limited in performance due to differences in pressure between the air and gas being mixed.

SUMMARY OF THE INVENTION An object of the present invention is to provide a gas conditioning apparatus in which the air supply is regulated to a pressure generally equal to the gas pressure thereby enabling accurate control of the mixing of the gas and air.

Another object of the invention is to provide a gas conditioning apparatus in which the air supplied to the device is dried thereby removing moisture from the air in order to provide a combustible mixture with a substantially reduced quantity of moisture entrained therein.

Yet another object of the invention is to provide an air conditioning apparatus in which the mixing chamber receiving the dried air and gas at substantially the same low pressure is provided with a plurality of spaced 'bafiles which requires the air and gas to move in a zig-zag path through the mixing chamber with the chamber also including screens therein to further intermingle and thoroughly mix and blend the gas and air so that a combustible mixture which is thoroughly mixed is discharged from the gas conditioning apparatus thereby providing an economical gaseous fuel mixture having a larger quantity of air incorporated with the gas than has been previously possible.

Yet another important object of the present invention is to provide a gas conditioning apparatus in accordance 3,711,256 Patented Jan. 16, 1973 with the preceding objects which is relatively simple in construction, easy to install, easy to control, effective and accurate in providing dried air and air and gas at a controlled pressure for effectively blending the air and gas mixture with the device being relatively inexpensive to manufacture and maintain in operation.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of the gas conditioning apparatus of the present invention illustrating schematically the components of the system and the orientation thereof.

FIG. 2 is a vertical, sectional view of the air and gas mixing chamber illustrating the relationship of the components disposed interiorly thereof.

FIG. 3 is a transverse, sectional view taken substantially upon a plane passing along section line 3-3 of FIG. 2 illustrating further structural details of the interior of the mixing chamber.

DESCRIPTION OF PREFERRED EMBODIMENT Referring now specifically to the drawings, the gas conditioning apparatus of the present invention is generally designated by the numeral 10 and includes a mixing chamber generally designated by the numeral 12 which is in the form of a vertically disposed circular tank 14 having a bottom 16 and a removable top 18 secured in place by bolts 20 extending through mating flanges with a gasket 22 disposed therebetween. The particular shape, size and configuration of the mixing chamber 12 may be varied without departing from the scope of this invention.

The upper end of the tank 14 is provided with an outlet adapter 24 to which an outlet pipe or conduit 26 is connected with the pipe or conduit conveying mixed air and gas to a point of use thereof. The opposite side and bottom of the tank is provided with a gas inlet adapter 28 having a gas inlet pipe or conduit 30 connected thereto and adjacent to the adapter 28, an air inlet adapter 32 is provided having an air pipe or conduit 34 connected thereto for introducing both air and gas into the tank adjacent the bottom thereof as illustrated in FIGS. 1 and 2.

Gas is supplied to the apparatus from a gas supply pipe or conduit 36 which supplies natural or manufactured gas to a gas meter 38 which discharges into the conduit 30. A gas pressure gauge 40 is provided in the gas line 30 and also incorporated therein is a vertically disposed conduit or pipe 42 having a gas pressure switch 44 at the upper end thereof which is disposed above the upper end of the tank 14 as illustrated in FIG. 1. The gas switch 44 serves to control the apparatus in response to the gas pressure in the supply line 30 so that in the event of a drop in the gas pressure below a predetermined low pressure, the gas pressure switch 44 will be activated for a purpose described hereinafter.

Air is supplied from an air line, conduit or the like 46 which may be connected to the discharge of a suitable compressor with the air line 46 having a conventional valve 48 therein and a pressure regulator 50 set at a predetermined pressure in order to supply air to an air receiving tank 52 at a predetermined pressure. As illustrated, the air receiving tank 52 is mounted horizontally on the removable top 18 of the tank 14 by a pair of brackets 54 with the conduit 46 communicating with one end thereof and the air supply conduit 34 benig communicated with the other end thereof. As illustrated, the conduit 34 extends vertically along tank 14 and then horizontally along the length of the air receiver tank 52.

Disposed in the horizontal portion of the air supply line 34 is an air filter 56', a solenoid control valve 58 and two tandemly arranged air drying devices 60 and 62. The air filter 56 is of conventional construction and may have a cleanable or replaceable filter element to remove any impurities, foreign particles or the like from the air. The solenoid valve 58 is electrically associated with the pressure switch 44 through a junction box 64 or the like so that when the pressure switch 44 is actuated, the solenoid valve 58 will be closed thus closing off air supply. The dryer units 60 and 62 also are commercially available units and may be of various types which remove moisture from the air. Such drying devices may be absorption type devices employing a desiccant or may incorporate electrical heating elements or other devices for removing moisture thereby providing a supply of dried air to the conduit 34 through a pressure regulator 66 and a shut-off valve 68 which may be closed when desired.

The air receiver tank is provided with a pressure gauge 70 and safetyplugs 72 therein which operate in the usual manner if the predetermined pressure is exceeded. Also, the tank or mixing chamber 14 is provided with a gas pressure gauge 74- therein and a gas temperature gauge 76 as illustrated in FIG. 2.

The interior of the tank 14 is provided with a plurality of vertically spaced baffles 78 and 80 with the baffies 78 being connected with a portion of the periphery of the tank and spaced therefrom at one edge as indicated at 82 while the baffles 80 are connected with the periphery of the tank in an area aligned with the space 82 and are spaced from the tank at the edge 84 thus providing a zig-zag path of movement for the air and gas after it enters the bottom of the mixing tank 14. It will be noted in FIG. 2 that the lowermost bathe 78 is disposed above the adapters 28 and 32 and that the passageway or space 82 is oriented remote from the point of entry of the air and gas. Also disposed between each of the bames is a plurality of spaced panels of fine screen wire 86 with the space between the panels 86 and the bafiles being substantially filled with or packed withmetallic wool 88 such as steel wool or the like. The combination of the bafiies, the fine screen panels 86 and the steel wool 88 provides a plurality of interstices through which the air and gas passes and produces a thorough intermingling and mixing of the air and gas as it passes upwardly from the point of inlet around the bafiies, in, around and through the various interstices defined by the screens and steel wool toward the point of discharge at the discharge adapter 24.

In the air receiver tank 52, a drain valve 53 may be provided for draining any moisture, sediment or the like which may collect in the tank and the safety plugs 72 may be incorporated into a relatively large removable in spection plug which can be removed for inspecting and possibly cleaning the interior of the air tank.

In operation, gas enters the mixing chamber 14 through the adapter 28 and dry air enters the mixing chamber 14 through the adapter 32 with the pressures of the gas and air being regulated so that the pressure is substantially equal. The air and gas are thoroughly mixed as they pass in a zig-zag pattern around the bafiies 78 and 80 and through the fine mesh screen 86 and steel wool 88. After the gas and dry air have been thoroughly mixed, the mixture is discharged from the mixing chamber 14 to the burners through the adapter 24 and pipe 26.

The pressure of the gas entering the mixing chamber controls the entrance of air into the mixing chamber through the pressure switch 44 which is so set that if the gas pressure drops below the working pressure, the

gas pressure switch 44 will be activated thus closing the solenoid valve 58 and cutting oflf air at that point thus assuring that at no time will air only be discharged into the mixing chamber 14 thus assuring that at no time will air only be discharged to the burners.

Compressed air enters the receiving tank from a suitable compressor with the pressure regulated in the tank to approximately 15 p.s.i. The compressed air outlet on the tank communicates with the filter 56 and the air passes therethrough and then through thesolenoid valve and dry units 60 and 62 which dry all the moisture out of the air before it enters the mixing chamber. The pressure regulator 66 on the air line 34 controls the air pressure to the mixing chamber 14 and is set to equalize the air pressure with the gas pressure supplied from the gas meter which is regulated to a predetermined pressure. As illustrated, the air tank '52 may also be provided with a pressure release valve 55 which will relieve any pressure in the tank which exceeds the predetermined maximum to prevent rupture of the tank and eliminate the rupture of the safety plugs 72 if safety plugs are used. In other words, the air receiver tank is a substantially standard air tank having the usual safety valve features and inspection plug features of predetermined size, shape and capacity.

The fact that theair pressure is reduced to a pressure equal to or substantially equal to the gas pressure and the air being dried enables a larger quantity of air to be incorporated into the gas and thus providing more economical combustible mixture.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

1. A gas conditioning apparatus for mixing air and gas at a point remote from a burner comprising a mixing chamber having an air inlet and a gas inlet communicated therewith and a mixed gas and air outlet having a pipe communicated therewith for supplying a combustible mixture to the remote burner, and means disposed completely interiorly oi the mixing chamber for mixing air and gas as it passes from the air and gas inlets to the outlet, said means including a plurality of transverse bafiies inthe chamber and being spaced from each other and oriented to require the air and gas to pass through the chamber in a zig-zag pattern, partition panels of fine screen in said chamber between said bafiles for further mixing of the air and gas as it passes through the chamber, and fine metallic wool disposed between the bafiles and screens and substantially completely filling the spaces therebetween to further mix the air and gas.

2. The structure as defined in claim 1 together with air valve means in the air inlet, and pressure responsive means communicating with the gas inlet and controlling the air valve means in response to gas pressure.

3. The structure as defined in claim 2 wherein said air inlet includes an air receiver tank and air drying meansbetween the tank and chamber to substantially remove all moisture from the air before it is mixed with gas.

4. The structure as defined in claim 3 together with air pressure regulating means to maintain the air pressure substantially equal to the gas pressure.

5. The structure as defined in claim 4 wherein said valve means is a solenoid operated valve, said pressure responsive means including a pressure switch actuated in response to low gas pressure to shut the valve means to prevent flow" of air when gas pressure tfalis below a predetermined low pressure.

6. The structure as defined in claim 1 wherein said mixing chamber includes a substantially vertically disposed tank having the air inlet and gas inlet adjacent the bottom of one side of the tank and the mixed gas and air outlet adjacent the upper end of the tank at the opposite side thereof, said tank having a removable top to enable installation of and replacement of the bafiles, screens and metallic wool, an air receiver mounted horizontally on the removable tank top and substantially within the vertical confines thereof, said air receiver including an air conduit extending therefrom to the air inlet, said air conduit including a pressure regulator, a solenoid control valve and an air dryer to supply regulated dried airto the mixing chamber, said gas inlet including a gas supply conduit communicated therewith, a gas pressure switch comm-unicated with the gas supply line and electrically connected to the solenoid control valve in the air supply conduit for cutting off the air supply to the mixing chamber when the gas pressure drops below a predetermined minimum thereby preventing the possibility of air only flowing through the mixing chamber and being supplied to a burner, said bafiles being disposed horizontally and vertically spaced [from each other within the vertically disposed tank with the space between adjacent baflles and between the endmost baffles and the ends of the tank having two screen partition panels therein separating the metallic wool with the baffies and partition panels being substantially equally spaced.